1. Field of the Invention
The present invention relates to a liquid crystal display panel. More particularly, the present invention relates to a liquid crystal display panel that prevents light from leaking in through the edges.
2. Descriptions of the Related Art
Traditionally, for liquid crystal (LC) materials in a liquid crystal display (LCD) panel to respond synchronously and consistently during operation, the LC materials are often subjected to an alignment process. That is, the major axes of the LC materials are formed at a predetermined angle with respect to the substrate, and thus, exhibit uniform orientation or oriented alignment.
In general, there are roughly three alignment modes for LC materials in LCD panels. The first mode, which is called the Homogeneous Alignment, sets the major axes of the LC materials so that they are parallel to the alignment film. The second mode, which is called the Heterogeneous Alignment or Vertical alignment, sets the major axes of the LC materials so that they are perpendicular to the alignment film. Lastly, the third mode sets the major axes of the LC materials so that they tilt at a certain angle (i.e. a pre-tilt angle) with respect to the substrate. Because the pre-tilt angle affects the LCD panel display characteristics, an alignment process is often conducted after the liquid crystal materials are interposed between the two substrates of the LCD panel. As a result, the LC materials are aligned at a predetermined angle. One of these alignment processes is called the “phase separation alignment (PSA)” process.
FIG. 1A illustrates a schematic top view on a second substrate 113 in an LCD panel 100 of a prior art, while FIG. 1B illustrates a schematic cross-sectional view of an LCD panel of the prior art. Referring to the prior art, the LCD panel 100 has an LC layer 119 interposed between the first substrate 111 and the second substrate 113. The LC layer 119 comprises LC materials 1191 and macromolecular polymers 1195 made from a photopolymerization process. The first substrate 111 and the second substrate 113 that are in a display area 101 have first electrodes 1151 and second electrodes 1153 disposed therein respectively, while the non-display area 103 at the edge of the display area 101 does not. Consequently, during the PSA process, the required voltage for alignment can only be applied in the display area 101 to align the LC material 1191 therein. In contrast, since there is no required voltage for alignment in the non-display area 103, the LC materials 1191 therein will tilt randomly as illustrated in FIG. 1B. The random tilt of the LC materials 1191 in the non-display area 103 leads to red light leaking in through the edges (e.g., at the border between the display area and the non-display area) of the LCD panel 100, which is especially significant when being viewed from the side. As a result, the panel display is no longer accurate.
Because LCD panels of the prior art do not align the LC materials at the edge of the display area, red light leakage commonly occurs when being viewed from the side. Thus, it is important for the LC materials at the edge of the display area to align during a PSA process so that the LCD panel is not subjected to the leaking in of red light from the edges.